Process of mordanting.



UNITED STATES PATENT OFFICE.

VICTOR LENDEOKE, OF LUDWIGSHAFEN, GERMANY, ASSIGNOR TO THE BADISCHEANILIN &; SODA FABRIK, OF SAME PLACE.

PROCESS OF MORDANTING.

SPECIFICATION formingpart of Letters Patent No. 671,894, dated April 9,1901.

Application filed March 29, 1899. Serial No. 711,027. (No Specimens.)

To all whom it may concern.-

Be it known that I, VICTOR LENDEOKE, a subject of the Emperor ofAustria-Hungary, residing at Ludwigshafen-on-the=Rhine, in the Kingdomof Bavaria and Empire of Germany, have invented new and usefulImprovements in Mordantin g Fibers, (for which applications for foreignpatents have been filed as follows: in Germany, No. B23,530, datedOctober 10, 1898; in England, No. 21,833, dated October 17, 1898, and inFrance, No. 271,354, dated November 28, 1898,) of which the following isa specification.

Under the name of chrome bisulfite a prbduct prepared by dissolvingfreshly-precipitated chrome oxid in aqueous sulfurous acid containingsome sulfuric acid is already used as a mordant. The presentinventionrelates to an improved process for fixing chrome oxid on cotton andother vegetable fibers, making use of the said product.

Although chrome mordants have been largely used for many years on animaland vegetable fiber, still all the processes for fixing chrome oxid foruse as a mordant on cotton and other vegetable fiber have suffered fromsome disadvantage or other. Some of the processes involved drying thematerial after treating with mordant solution and were consequentlyexpensive. In some of them it was difficult to obtain even shades, sothat although applicable to piece goods and other cases where it waspossible to insure an even application of the mordanting solution stillthey were not applicable to cotton yarn, loose cotton, or the like.Again, when mordanting by some of the old processes for fixing chrome onthe fiber the chrome oxid, although precipitated on the fiber, would notadhere to it, but was liable to be washed away when swilling the goods.

The present invention affords a cheap method of fixing chrome oxid oncotton or other vegetable fiber in such a way that uniform dyeings canbe subsequently obtained even on cotton or other vegetable yarns andloose cotton or other vegetable fibers. It can also be applied to piecegoods with advantage.

The main feature of the process consists in impregnating the material tobe mordanted with a comparatively dilute solution of chrome bisulfiteand subsequently treating the goods without previous drying with analkaline salt, by which term I mean a salt which is alkaline tolitmussuch, for instance, as carbonate or bicarbonate of soda, carbonateof potash, phosphate of soda, or the likewhen the fixing of the chromeon the fiber takes place quite evenly.

The following example will serve to illustrate the manner in which myinvention can best be carried into practical effect: Take about onehundred kilograms of cotton yarn, which have been previously thoroughlyboiled and wrung out in a centrifugal machine, and steep them forseveral hours, preferably over night, in a chrome-bisulfite solution of10 Baum, wring out the goods thoroughly, and free them from excess ofchromebisulfite solution by treating them in a centrifugal machine. Thenwithout drying pass them for about ten to fifteen minutes through a bathcontaining about three grams of calcined soda for every liter of waterand which is maintained at a temperature of centigrade. Wash the goods,treat them once more in the centrifugal machine, and then steep them ina solution which contains about one hundred grams Turkey-red oil forevery liter of water and then dry.

The unabsorbed chrome-bisulfite solution can be used repeatedly, onlysufficient fresh concentrated solution must be added after eachoperation to bring it to the desired strength. Goods mordanted with achromebisulfite solution of the aforesaid strength yield dark shadeswhen dyed. For medium shades the mordanting-bath need only be of 5 Baumand for light shades of 3 Baum. The quantity of soda in the fixing-bathcan also be diminished in a corresponding manner. The process, asillustrated by the above example, can be applied to loose cotton and tocotton piece goods and also to linen and hemp. Instead of soda othersalts which act as alkalies, such as those aforementioned,can be used.

Now what I claim is-- The process of mordanting vegetable fiber by meansof an aqueous solution of chromium my hand in the presence of twosubscribing bisulfite, which consists in impregnating the Witnesses.

'oods to be dyed with this solution and passing the goods in the Wetcondition through a VICTOR LENDEGKE' 5 bath containing ahereinbefore-defined alka- Witnesses:

line salt, substantially as described. GUSTAV L. LUTTENBERGER,

In testimony whereof I have hereunto set ADOLPH REUTTINGER.

